Ashutosh, who joined the party in 2014 after being a journalist for 23 years, took to Twitter to announce he was quitting and thanking the party for its support.

"Every journey has an end. My association with AAP which was beautiful/revolutionary has also an end. I have resigned from the party (and) requested (it) to accept the same," he tweeted.

"It is purely from a very very personal reason. Thanks to (the) party (and those) who supported me throughout. Thanks," he added.

In another tweet, he asked the media to respect his privacy.

Retweeting Ashutosh's tweet, Kejriwal said he cannot accept the resignation, at least in this lifetime. "How can we ever accept your resignation? No, not in this lifetime."

In another tweet, he said: "Ashutosh sir, we all love you a lot."

Ashutosh had expressed unhappiness over the choice of two of the three nominees to the Rajya Sabha. Once seen as close to Kejriwal, he had mostly kept away from party activities since then.

Ashutosh was the AAP candidate from Delhi's Chandni Chowk constituency in the 2014 Lok Sabha polls and finished runner-up to BJP's Harsh Vardhan.

For 2019, Pankaj Gupta, a party spokesperson, has been chosen as the 'prabhari' of Chandni Chowk and most likely will be the candidate as well.

Sanjay Singh, MP and a member of the party's Political Affairs Committee of which Ashutosh was a member, called the resignation "heartbreaking".

"My association with Ashutosh as a friend and trustworthy partner will be lifelong. His separation from the party is a heartbreaking news for me," he said, adding he will request him to take back the resignation.

Delhi cabinet Minister Gopal Rai called the decision "sad".

Party's chief spokesperson Saurabh Bhardwaj said his resignation had not been accepted yet and he had been asked to reconsider his decision.

Support for Ashutosh poured in from other party leaders as well.

Delhi MLA from Dwarka Adarsh Shastri described him as a source of inspiration and urged him to reconsider his move.

Sushil Gupta, one of the Rajya Sabha MPs who Ashutosh did not approve of, tweeted: "I have high regards and respect for Ashutoshji, his contribution in the victory of Delhi election and strengthening of AAP nationwide are unmatchable. I appeal him to rethink his decision."

Ashutosh is the latest in a series of senior leaders to quit the AAP, which has ruled Delhi since 2015. Those who exited earlier included Yogendra Yadav, Prashant Bhushan, Mayank Gandhi, Anjali Damania, Anand Kumar, Ajit Jha and Shazia Ilmi.